Spring support for motor vehicles



R. W. POINTER SPRING SUPPORT FOR MOTOR VEHICLE June 27, 1944,

Filed Sept. 25, 194i 2 Sheizs-Sheei: l

. ROBERT w. POINTER ATTORNEY June 27, 1944.' w. POINTER SPRING SUPPORT FOR MOTOR VEHICLE Filed Sept. 23, 1941 Z'Shets-Sheet 2 ATTORNEY Patented June 27, 1944 UNITED STATES PATENT OFFICE SPRING SUPPORT FOR MOTOR VEHICLES Robert W. Pointer, Portland, Oreg.

Application September 23, 1941, Serial No. 411,954

'1 Claims. (Cl. 267-20) The present invention relates to spring supports for motor vehicles, and, while it is not necessarily limited thereto, it is particularly applicable for mounting the wheels of truck and trailer vehicles.

Certain types of vehicles such as trucks are subject to a great diiierential in weight between the empty and full load conditions. Generally, the spring supporting structure for such vehicles is designed to provide a relatively smooth ride for the fully loaded vehicle. Accordingly, the springs of such structures are relatively still, and, when pended claims. g In the drawings, Figure 1 is an outlinesketch the point of delivery, and the severity of road' shocks is considerably increased at such times, due to the fact that when empty the vehicles usually are driven at higher rates of speed than when fullyloaded. Unless provision is mad in the spring suspension arrangement for properly cushioning the vehicle against road shocks when traveling light, the vehicle structure is apt to be literally shaken apart. "I

It is, therefore, an object of the present invention to provide a newanil improved spring supporting arrangement for motor vehicles which will provide adequate cushioning of road shocks under both light and heavy load conditions.

' It is a further object of the invention toprovide a spring support for motor vehicles so constructed and arranged that side sway oi the vehicle when negotiating curves, and, consequently much tire wear, is eliminated.

It is a further object of the invention to provide a novel spring support for motor vehicles, and particularly for trucks and trailers, which is. of a relatively simple construction, comprising relatively few parts, and which is economical o Fmanufacture. v

In accordance with an illustrated embodiment of the invention, a lever arm extends longitudinally beneath eachside or, the vehicle frame and is pivotally connected thereto for movement in the vertical plane of the side'frame member. A shaft for the vehicle wheels is mounted upon the lever intermediate its ends. .A first, relatively light, coil spring is arranged between th lever and the frame and is eilective for supporting and providing adequate cushioning for the vehicle. when empty or only lightly loaded. A second coil spring, also arranged between the lever and the vehicle irame, is of a relatively heavy size and is capable of supporting the vehicle .and pro: viding adequate cushioning of road shocks therefor when fully loaded. The second spring is so mounted that it is normally unstressed during the light load condition of the vehicle, but upon application of full load thereto' the heavy, spring.- becomes effective in parallel relation with the first spring. --A shock absorber is further connected between the-lever army and the vehicle frame for dampening the rebound.

For a consideration of what is believed novel and inventive, attention is directed to the follow" ing description and the claims appended thereto, taken in connection with the accompanying drawings, while the features of novelty will be pointed out with greater particularityv in the apillustrating a truck type trailer having a pair of rear wheels supported by a suspension structure according to the present invention; Figure '2 is an enlarged view of the suspension structure,

illustrating the relative position of parts during a fully loaded condition of the vehicle; Figure is a view in perspective, a part thereof being 7 broken-away, illustrating in further detail the construction for the lever arm .of the supporting arrangement; Figure 4.is a rear view of the trailer shown in Figure 1; Figure 5 is a plan view of .a port on of a vehicle framework having pairs; of tandem wheels mounted thereon with a suspension structure according to a modification of the invention; and Figure 6 is a view taken along the line 6-6 of Figure 5.

Referring to the drawings, the n'umeralll indicates a truck type trailer vehicle having a 1 main frame comprising side members II, forward wheels l2, and rear wheels II. The rear wheels IS in this instance are mounted on the vehicle with a spring supporting arrangement constructed in accordance with one form; of the present invention. As shown more clearly in Figure 2, the supportingarrangement comprises a relatively rugged lever arm I! which is pivotally mounted as at It upon the bracket ll depending from the side frame member H. The lever arm I! extends'longitudinally be'- neath the side frame member II and is'plvotally movable about the point It in, the vei- The lever arm It may be of any suitable construction": for v tical plane of the framev member ll.

example, as shown in Figure 3, it may be of boxshaped cross section tor imparting requisite strength and rigidity thereto- The lever arm is relatively wide, particularly at its forward end through which the pivot pin extends, so that the pivotal connection will permit of substantially no lateral movement of the lever arm. r The wheel shaft i8 is resiliently mounted upon the lever arm Ii intermediate-the ends of' the latter, the shaft extending transversely with"re'- A first, relatively light spring 2| 'is arranged between the vehicle frame member H and the lever arm I! above the shaft it. The opposite ends of the spring ;2l engage with the cooperating seats 22 and-23 secured to the facing surfaces of the frame member H and the lever arm ll, re spectively. Suitably secured to the outer surfaces of the seats 22 and 23 are round blocks 2i and 25, respectively, which extend concentrically within the corresponding ends of the spring 2| so as to retain the spring in place. ,These blocks maybe of a resilient material such as rubber so that they will act as buffers to prevent direct me-' tallic contact between the two relatively movable parts, as when the wheel suddenly passes over an obstruction.

A relatively. heavy second spring 21 is mounted mile i so that a relatively small shock absorber acting through the long lever arm will provide adequate snubbing of the relative movements between the arm "and thevehicle frame. -In this latter re-' gard, it will be observed that the heavy, load spring 21 also is arranged preferably toward the end of the lever arm is whereby the use of a considerably lighter spring is permissible than if it were arranged closer to the shaft. In the position shown the shock absorber 25 is also eifective to prevent side sway of the vehicle when negotiating curves. The snubbing of the movementhetween the arm I8 and the vehicle frame holds v the frame level and, skidding transversely of the sorber also ties the arm l5 to the vehicle frame upon the arm I! on the opposite side of the first the, frame H in parallel relation with the first spring 2| as regards the pivot II, and which spring 21 extends between the lever arm ll and roadway is largely overcome. The shock abto prevent excessive separation therebetween, and thereby precludes the possibility of the springs 2| and 21 becoming dislodged during the period of rebound. Itwill readily be understood that the relative position of the springs 2| and 21 may be reversed if desired, that is, the long, light load spring 2| may be arranged at the end of the arm |I and the shorter heavy load spring 21 arranged ,above the shaft. Such an arrangement might be preferred when the weight differential between the empty and fully loaded condition of the truck is considerably less than in the case first assumed.

spring 2|.- Seats 28 and 2! for the opposite ends so with the springs mounted as described, it will of the spring 21 are provided on the lever and II and the frame member ii, respectively, cylindrical blocks ii and 22 being suitably secured to the facing surfaces thereof and which extend con-.

- centrically into the opposite ends of the spring 21 for retaining the latter spring in place. The

spring 21 is of such a length as regards the length of spring 2| so that during the empty condition of the vehicle or during the extremely light load condition thereof, the upper endof the spring 21 is spaced from the upper seat 22. Thus, during the empty or light loaded condition of the fective in supporting the weight of the vehicle and for cushioning the road' shocks which may. be transmitted thereto. Upon the application of vehicle the relatively light spring 2| is solely effull load to the vehicle, the relatively light sprins 2| will be compressed to such an extent astoal- "low the upper seat 2! to engage withthe upper end of the heavier spring 21. It will be observed that the upper block 22 is of a length greater than the spacing between the seat 2| and the upper end of the spring 21 so that it projects thereinto durin'g' the empty condition of, the vehicle guides the, upper end ofthe spring '21 into proper seatlnarelation'withthe seat "as the vehicle is loaded. Thus, during the fully loaded condition" of the'vehicle, the two springs M and 2] are effective in parallel relation for .supP0rting the weight, spring :1 being soselected that,

when acting in conjunction with spring 2|, the

road shocks are smoothly cushioned. Blocks 3| and-32, and-particularly the latter, maybe of a resilient material such as rubber, if desired, so that they may act as buffers in the event spring 21 is compressed to the extent that these blocks contact with each other.

For checking the rebound of the vehicle frame following e over a surface irregularity in the roadway, a suitable shock abmrber il including a link It is connected between the vehicle frame H and an outer extremity. of the lever arm II. It will be observedthat the point of connection of the shock absorber to thearm is thus considerably removed from the shaft ll jmit the springs to be lifted off of the'seats and others to be substituted therefor. No special skill, tools, or shop equipment is necessary to effect such asimple change. Furthermore, the

change may be performed within a very short period of time,

As'illustrated'in Figures 1 to 4, inclusive, the of rear wheels I: are .mounted upon a single shaft l8, while the vehicle is mounted'upon the one shaft by means of a pair of similar spring supporting structures. The spring supporting structures, as described, are also suitable for mounting the vehicle frame upon dual wheel units as illustrated in Figures 5 and 6. In this in-. stance, the pairs of dual wheels 4| are mounted in a spaced relation upon individual short shafts l2. The lever .arms II are in turn suitably mounted upon the'shafts 42 between the wheels 4|, as by a cushion mount further described in.

the above mentioned patent. The pivotal connection with the side frame members H is sufficiently rugged as to amply withstand any relative side thrusts between the undercarriage and the vehicle framework.

It will be apparent that the spring supporting arrangement as described is effective in providing adequate cushioning of road shocks for all conditions 'of; load, and thus is particularly suitable for on such vehicles having superstructures .which are inherently incapable/of withstanding severe vibrations. 1 y

Having described my invention in what-I consider to be a preferred embodiment, I desire to of said arm on the opposite side of said first coil spring with respect to said pivotal connection, said second coil spring beingunstressed during light vehicle load conditions and adapted to be compressed between said armand said frame member during normal heavily loaded vehicle conditions,'and a shock absorber connecting the outer'end of said arm and said frame member. 2. In a vehicle, a main frame member, a lever arm pivotally connected at one end to said member and extending longitudinally therebeneath, said pivotal connection permitting movement of said arm in the vertical plane of said frame member and substantially precluding movements of said arm in a horizontal direction, a shaft mounted on said arm intermediate its ends, a relatively light coil spring arranged between said arm and said member and normally under compression therebetween, a second coil spring mounted on said arm on the opposite side of said first coil spring with respect to said pivotal connection, said second coil spring being spaced from said member and unstressed during light vehicle load conditions and adapted to engage with said frame member during normal heavily loaded vehicle conditions, and a shock absorber connecting the end of said arm and said frame member remote from said pivotal connection.

heavily loaded vehicle conditions, and means including a. buffermember secured to said frame member extending downwardly concentrically within said second coil spring.

5. In a vehicle, a main frame member, a lever arm pivotally secured at one end to said frame member and extending longitudinally therebeneath, a shaft mounted transversely of said arm intermediate its ends, a coil springarranged between said arm and said member and under conpression therebetween, a second coil spring mounted on said arm on the opposite side of said first coil spring with respect .to said pivotal connection, the upper end of said second spring being spaced from said member during light vehicle load conditions and adapted to be compressed between said frame member and said arm during heavily loaded vehicle conditions, and means comprising a resilient buffer member secured to said frame member and extending downwardly therefrom concentrically within said second spring during light vehicle load conditions, and a second buffer member secured to said arm within said second coil spring adapted to engage with said first bufler member and for retaining said second spring upon said arm.

6. In a vehicle, a main frame member, a lever arm pivotally connected at one end to said frame 3. In a vehicle, a main frame member, a lever -arm pivotally connected at one end to said frame member and extending longitudinally therebeneath, a shaft mounted on said arm intermediate its ends, a first, relatively light coil spring arranged between said arm and said member and under compression therebetween, a second, relatively heavy coil spring mounted on said arm on the opposite side of said first coil spring with i'espect to said pivotal connection, the upper end of said second coil spring being spaced from said vehicle frame member during light vehicle load conditions and adapted to be compressed between said frame member and said arm during heavily loaded vehicle conditions, and means secured to said frame member extending downwardly a relatively short distance into the upper end of said second coil spring. for guiding said second spring into engagement with said frame member during heavily loaded vehicle conditions.

4. In a vehicle, a main frame member, a lever arm pivotally connected at one end to said frame member and extending longitudinally therebeneath, a shaft mounted transversely of said arm intermediate its ends, a first coil spring arranged between said arm and said member and normally under compression therebetween, a second coil spring mounted on said arm on the opposite side of said first coil spring with respect to said pivotal connection, the upper end of said second coil spring being spaced from said vehicle frame member during light vehicle load cpndltiom and adapted to be compressed between saidframe member and said arm during member and extending longitudinally therebeneath, a wheel shaft mounted on said arm intermediate its ends, a first relatively light coil spring arranged between said arm and said member and normally compressed by said arm and member, a second relatively heavy coil spring mounted on said arm on the opposite side of said first coil spring with respect to said pivotal connection, the upper end of said second spring being spaced from said frame member during light vehicle load conditions and adapted to be compressed between said frame member and said arm during heavily loaded vehicle conditions, a seat for the upper end of said second spring secured to said frame member, and buffer blocks secured to the facing surfaces of said frame memher and said arm and extendinginto the opposite ends of said second spring for retaining said spring in place and 101 guiding the upper end of said second spring onto said said seat upon the application 01' full load to said vehicle.

I. In a'vehicle, a main frame member, a lever arm pivotally connected at one end to said frame a member and extending longitudinally therebeneath, a shaft mounted transversely of said arm intermediate its ends, a first coil spring arranged between said arm and said member, seats on said member and said arm 10]. the opposite ends of said first coil spring, means secured to said seats lor loosely retaining said nrst coil spring on said seats, said first con spring being held under compression between said seats, a second relatively heavy coil spring mounted between said arm and said frame member and spaced from said first coil spring, seats for said second coil spring on said frame member and said arm, one end of said second coil spring being spaced from the corresponding one of said seats during light vehicle load conditions, means secured relative to said one seat for guiding said spaced and of said second coil spring onto said one seat upon application of full load to said vehicle and loosely retaining said second spring upon the opposite of said seats, and means ,including a shock absorber connecting the end of said arm opposite said pivotal connection to said frame member.

- ROBERT W. POINTER. 

